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C00002 00002	The system program VARIAN outputs data to the Varian Plotter (device VRN)
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The system program VARIAN outputs data to the Varian Plotter (device VRN)
from files properly formatted for this purpose.

This program takes a sequence of up to 15 (decimal) files of mostly raw
raster data and outputs the files, concatenated, to the VRN in dump mode.
The drawing will be centered on the VRN.  An optional outline can be drawn
around either the whole drawing or every group of N files in the drawing.
In order to be able to provide the dump-mode data to the VRN as fast as
possible, this program uses overlapped mode (mode 117) and opens all the
specified files before output to the VRN is begun.

The program first asks about outlining the drawing and then requests the
name(s) of the file(s) you want to print.  The outlining options are:
(1) no outlining -- print the concatenation of all the files without
intervening blank paper; (2) make one outline around the concatenation of
all the files; (3) make a separate outline around every group of N files
(where N is from 1 to 9 inclusive) -- in this case a small amount of
blank paper is run out between outlined groups.  Up to 15 files can be
printed, using one of the above outlining options.  The program will ask
for one filename at a time; when you have finished typing in all the
filenames, type just carriage return to the "File:" prompt to signify the
end of the file list.

If there are any errors in the VRN output, the program will report and
interpret the error data returned by the system.  You can then have
the program retry printing the entire collection of files previously
specified by saying CONTINUE to the monitor.

If device VRN is not available, this program will wait for it, with an
appropriate message when it begins to wait.

The data format in each file to be printed is as follows (files in this
format can be written by the XGPSYN/XGPSYG programs, see HPM for more
details):

	The first 200 (octal) words of each file contain general parameters
	for the whole file.  The parameters used by this program are:
		Word 2/	words of file per scanline
		Word 4/ number of scanlines of data in file
		Word 6/ bits of actual data per scanline, + 37 (decimal)
	(Note: "Word 2" means the third word of the file.  The first word
	of the file is Word 0.)

	If an outline is to be made, every file must have the same value
	in word 2 of these parameters and the number of bits of actual
	data per scanline (from word 6) must be less than or equal to the
	actual width of an entire VRN scanline (currently claimed to be
	=4224); also, the words per scanline (word 2 of file) must be
	sufficient to include the number of bits of data given by word 6,
	or else no outline can be drawn.  Word 6 is used to determine
	where to draw the right margin line, and how to center the drawing
	on the VRN.  If the requirements for outlining are not met, this
	program will make the drawing without the outline (after typing
	a warning message to that effect).

	Each entire file after the first 200 words consists of continguous
	blocks, one per scanline, of raster data, with each block
	containing as many words as indicated by word 2 of the file.  The
	first word of each block, however, is not taken as raster data,
	but is ignored (a VRN dump-mode Group Command Word is placed there
	to tell the system how much raster data follows).